"A suicide bomber blew himself up in a crowd of mourners in northern Iraq on Thursday, killing at least 45 people," a police officer told AFP.
"The man detonated an explosives vest in the crowd in the Sunni Arab village of Bu Mohammed, 120 kilometres south of the oil city of Kirkuk at around 11:00 am (local time)," Captain Abdullah Jassim said.
Doctor Jawdat Abdullah from the hospital in Al-Tuz, near Bu Mohammed village, confirmed the attack, saying his facility was receiving the wounded, some of whom were seriously hurt.
Jassim said that the crowd had gathered to present their condolences over the deaths of two members of a local group fighting Al-Qaeda in Iraq who were killed two days ago.
Tens of thousands of Sunni Arabs have formed local groups across Iraq backed by the US military to battle Al-Qaeda militants.
These groups, mostly former allies of Al-Qaeda, have been increasingly targeted by the jihadist group in the past several months.
Imad Abdullah al-Azzawi, a witness who survived the suicide attack said the bomber blew himself inside the tent where the condolence meeting was taking place.
"There are bodies and body parts scattered everywhere. There is blood everywhere," he told AFP.
The latest attack came just two days after a suicide bomber killed at least 13 people in the western city of Ramadi, a former stronghold of Sunni insurgents.
Several of those killed were also members of a local anti-Qaeda group in Ramadi, the capital of the Sunni Arab province of Anbar.